we have POS System which is using Mobilink (ver 9.X) to synchronize the data to console server ( Sybase ASE ver 12.5) . user complained that the POS system hangs( freeze application screen) intermittently . we did a test and found that the screen freezes while user settled transaction and at the sametime mobilink client waiting for apply upload to console server . is there any suggestion to improve this situation.

If your remotes are SQL Anywhere, consider using transactional uploads (this link is for v10, but the option should behave in much the same way, if not identically). It will only help if your remote used many transactions to make the upload. There will be no benefit if the upload represents a single transaction from the remote. While the upload, and hence the sync, may take longer, being many transactions instead of one, the contention in your consolidated database will be reduced.

Just to clarify: "Transactional uploads" doesn't mean each transaction is "automatically" sync'ed against the consolidated database. Synchronization does simply just happen at the same schedule or events it woud without transactional uploads.